スイクン suikun sui ‐>swee
I feel this one is justifiable.
Zapdos, I don't think i've ever heard of anyone saying Zapados... It's literally two syllables (Zap-Dos).
Poké-mon, the mon in English is pronnounced like Mon in Monsters. In Japanese it's モン which is still mon but pronnounced like "moan". Because it also comes from the word Monster, just the Katakana version instead so モンスター(monsuta-). So if it's an English speaker than obviously they're going to pronounce the English way.
The Gyarados nitpick is accurate tho. Even in Japanese they say ギャラドス (Gyaradosu), so not Gary but Gyara.
Flareon, also an accurate nitpick. But I can undertand the mixup. Best way to tell someone to say it right by (Flar, as in Flare, and eon. COMBINED you get Flareon).
Real nitpick is Arceus localized pronunciation. Why Ark-key-yus not Arseeus?? Japanese name is アルセウス which in romaji is Aruseus, pronnounced like "Ar-sues". Which is closer to ar-see-us in English.